Figure-7.115 shows the top view of a cylindrical can \( \mathrm{P} \) mounted on a turntable. Th...

Figure-7.115 shows the top view of a cylindrical can
\( \mathrm{P} \) mounted on a turntable. The can is filled with water. At a depth W \( h \) below the water surface are two horizontal tubes of length \( l \) and cross-sectional area \( a \), with right-angle bends at their ends. Show that, as the water jets emerge from the tụbes, there is a torque \( \tau \) exerted on the system given by the expression \( t=4 \rho g h \) \( (r+l) a \), where \( \rho \) is the density of the water.